Many recent scientific studies have shown the effectiveness of taking supplements with the proper combination of Glucosamine, Chondroitin, MSM (methylsulfonylmethane) and Hyaluronic Acid. These compounds found in the soft cartilage, tendons, and synovial fluid, are essential to the healthy functioning of tendons and joints, especially with advancing age. 21st Centurys Glucosamine & Chondroitin PLUS, combines these nutritional elements in the proper amounts for your effective use.